Multi-wavelength observations of IGR J17544-2619 from quiescence to outburst
Journal
Date Issued
2016
Author(s)
Bozzo, E.
•
Bhalerao, V.
•
Pradhan, P.
•
Tomsick, J.
•
•
Ferrigno, C.
•
Chaty, S.
•
Oskinova, L.
•
Manousakis, A.
•
Walter, R.
•
Falanga, M.
•
•
•
Ramolla, M.
•
Chini, R.
Abstract
In this paper we report on a long multi-wavelength observational campaign of the supergiant fast X-ray transient prototype IGR J17544-2619. A 150 ks-long observation was carried out simultaneously with XMM-Newton and NuSTAR, catching the source in an initial faint X-ray state and then undergoing a bright X-ray outburst lasting approximately 7 ks. We studied the spectral variability during outburst and quiescence by using a thermal and bulk Comptonization model that is typically adopted to describe the X-ray spectral energy distribution of young pulsars in high mass X-ray binaries. Although the statistics of the collected X-ray data were relatively high, we could neither confirm the presence of a cyclotron line in the broad-band spectrum of the source (0.5-40 keV), nor detect any of the previously reported tentative detections of the source spin period. The monitoring carried out with Swift /XRT during the same orbit of the system observed by XMM-Newton and NuSTAR revealed that the source remained in a low emission state for most of the time, in agreement with the known property of all supergiant fast X-ray transients being significantly sub-luminous compared to other supergiant X-ray binaries. Optical and infrared observations were carried out for a total of a few thousand seconds during the quiescence state of the source detected by XMM-Newton and NuSTAR. The measured optical and infrared magnitudes were slightly lower than previous values reported in the literature, but compatible with the known micro-variability of supergiant stars. UV observations obtained with the UVOT telescope on-board Swift did not reveal significant changes in the magnitude of the source in this energy domain compared to previously reported values.
Volume
596
Start page
A16
Issn Identifier
0004-6361
Ads BibCode
2016A&A...596A..16B
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
2016AA.596A.16B.pdf
Size
1.81 MB
Format
Adobe PDF
Checksum (MD5)
000d97c13b9978e75c89e573250eeaf0